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3 years ago

Please help me with this question.

Mathematics

1 answer:

CaHeK987 [17]3 years ago

4 0

Answer:

Step-by-step explanation:

Let's say that R, N, and M are the ages of Ric, Nancy, and Michael in 1980.

We can write three equations:

R = 2N

N = 2M

(R + 12) + (N + 12) + (M + 12) = 78

Simplify the third equation:

R + N + M + 36 = 78

R + N + M = 42

Substitute the first equation:

2N + N + M = 42

3N + M = 42

Substitute the second equation:

3(2M) + M = 42

6M + M = 42

7M = 42

M = 6

Therefore:

N = 12

R = 24

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2.8 meters linen divided into 45 cm pieces = # of pieces and waste

pogonyaev

2.8 meter= 2800cms

To solve this, we can create a simple algebraic equation:
45x=2800
Divide both sides by 45.
(45x)/45=(2800)/45
x=62.222

You can make 62 full pieces.

To find the waste, multiply the numbers of pieces by the length of each.
62*45
=2790
2800-2790
=10 centimeters

There would be 10 centimeters of wasted linen.

Hope this helps!
-Benjamin

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3 years ago

Arianna gathered data about the distance of 20 cities from the equator and the average hours of sunlight per day in December for

stich3 [128]

Answer-

A. strong negative correlation.

Solution-

Direction of a relationship

Positive- If one variable increases, the other tends to also increase. If one decreases, the other tends to also. It is represented by positive numbers(i.e 0 to 1).
Negative- If one variable increases, the other tends to decrease, and vice-versa. It is represented by negative numbers(i.e 0 to -1)

Strength of a relationship

Perfect Relationship- When two variables are linearly related, the correlation coefficient is either 1 or -1. They are said to be perfectly linearly related, either positively or negatively.
No relationship- When two variables have no relationship at all, their correlation is 0.

As in this case, correlation coefficient was found to be -0.91, which is negative and close to -1, so it is a strong negative correlation.

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3 years ago

4 3/10 - ( 2 2/5x+ 5 1/2) = 1/2(-3 3/5x + 1 1/5)

koban [17]

Answer:

x = -223/11 = -20.273

Step-by-step explanation:

Step 1 : Simplify: 11/5

Step 2: Simplify 33/5

Step 3 :

Adding fractions which have a common denominator

Step 4: Simplify: 1/2

Step 5 : see below

Step 6 : see below

Pulling out like terms/factors

Step 7 : Simplify: 51/2

Step 8: Simplify: 22/5

Step 10: Simplify: 43/10

Step 9 :

Calculating the Least Common Multiple

Step 11 :

Adding fractions which have a common denominator

Done.

Hope this helps.

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3 years ago

When calculating the successive discounts of 15% and 10% on a $100 item, _____. a. take 10% of $85 b. take 10% of $90 c. take 15

LekaFEV [45]

10% of 100$ is the answer

7 0

3 years ago

Read 2 more answers

Name

Sedaia [141]

Answer:

Step-by-step explanation:

19% of 72 = about 14%

42% of 16 = about 7%

47% of 118 = about 55%

67% of 296 = about 198%

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3 years ago